钒钛磁铁矿内配骨料气基还原试验  

Experiment on gas-based reduction of adding aggregate in vanadium-titanium magnetite ore

作　　者：代文林 邢相栋[1,2] 苗红生 张宝婷[4] 卞卫新 折媛 DAI Wenlin;XING Xiangdong;NMIAO Hongsheng;ZZHANG Baoting;BIAN Weixin;SHE Yuan(College of Metallurgy Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,Shaanxi,China;Metallurgical Engineering Technology Research Center of Shaanxi Province,Xi'an 710055,Shaanxi,China;Xining Special Steel Co.,Ltd.,Xining 810005,Qinghai,China;Hanzhong Iron and Steel Co.,Ltd.,Shaanxi Iron&Steel Group,Mianxian 724200,Shaanxi,China)

机构地区：[1]西安建筑科技大学冶金工程学院,陕西西安710055 [2]陕西省冶金工程技术研究中心,陕西西安710055 [3]西宁特殊钢股份有限公司,青海西宁810005 [4]陕西钢集团汉中钢铁有限责任公司,陕西勉县724200

出　　处：《中国冶金》2024年第5期37-44,81,共9页China Metallurgy

基　　金：国家自然科学基金资助项目(52174325);陕西省创新能力支撑计划资助项目(2023-CX-TD-53);陕西省教育厅重点实验室科学研究计划资助项目(20JS072)。

摘　　要：气基还原工艺处理钒钛磁铁矿逐渐受到研究者的关注,但目前该工艺还原后的钒钛磁铁矿金属化率较低。针对气基还原钒钛磁铁矿金属化率低的问题,以兰炭为骨料研究兰炭添加量、还原气氛、还原温度、还原时间等因素对钒钛磁铁矿气基还原金属化率及抗压强度的影响,并运用X射线衍射(XRD)和扫描电镜(SEM)方法分析了还原产物物相变化及微观形貌变化,总结出兰炭的作用机理。结果表明,添加兰炭可提升钒钛磁铁矿气基还原的效果,在还原气氛φ(H_(2))/φ(CO)=2.5、还原温度1 100℃、还原时间60 min条件下,未添加兰炭时试样金属化率仅为81.78%;在同样条件下,当兰炭添加量(质量分数)为6%时,试样金属化率可达到92.35%。钛铁化合物还原历程为Fe_(2.75)Ti_(0.25)O_(4)→Fe_(2)TiO_(4)→FeTiO_(3)→FeTi_(2)O_(5)→TiO_(2)和Fe,随着还原温度升高,金属铁相逐渐聚集连接成片,渣相与铁相分离明显。添加兰炭还原后试样内部的孔隙数量明显增多,促进还原气体向试样内扩散,推动还原继续进行,最终提高试样的还原效果。研究结果也为气基还原钒钛磁铁矿提供了理论指导。The treatment of vanadium-titanium magnetite ore by gas-based reduction process has gradually attracted the attention of researchers.However,the metallization rate of vanadium-titanium magnetite ore reduced by this process is low at present.Aiming at the problem of low metallization rate for gas-based reduction of vanadium-titani-um magnetite ore,the effects of the amount of semicoke,reduction atmosphere,reduction temperature and reduc-tion time on the metallization rate and compressive strength of gas-based reduction for vanadium-titanium magnetite ore were studied using semicoke as aggregate.The phase change and microstructure change of the reduction product were analyzed by X-ray diffraction(XRD)and scanning electron microscopy(SEM),and the mechanism of semi-coke was obtained.The results show that the addition of semicoke can improve the effect of gas-based reduction of vanadium-titanium magnetite ore.Under the conditions of reduction atmosphere φ(H_2)/φ(CO)=2.5,reduction temperature 1l 100℃and reduction time 60 min,the metallization rate of the sample without semicoke is only 81.78%.Under the same conditions,when the addition amount of semicoke is 6%,the metallization rate of sample can reach 92.35%.The reduction process of titanium-iron compounds is Fe_(2.75)Ti_(0.25)O_(4)→Fe_(2)TiO_(4)→FeTiO_(3)→FeTi_(2)O_(5)→TiO_(2) and Fe,with the increase of reduction temperature,the metal iron phase gradually gathers and con-nects into a piece,and the slag phase is obviously separated from the iron phase.After the addition of semicoke,the number of pores inside the sample increases significantly,which promotes the diffusion of reducing gas into the sample,promotes the reduction to continue,and finally improves the reduction effect of the sample.The research result provides theoretical guidance for gas-based reduction of vanadium-titanium magnetite ore.

关 键 词：钒钛磁铁矿 气基还原 兰炭 骨料 金属化率 

分 类 号：TF55[冶金工程—钢铁冶金]